How Doctors Diagnose

Several months ago a friend of mine, whom I'll call Olivia, asked me for some medical advice. She had just spent the day in an emergency room for treatment of severe pelvic and ovarian pain. The ER doctor told Olivia that she had a ruptured ovarian cyst. In the ER workup, through an MRI and x-rays, it was discovered that Olivia had a spot or cyst on her kidney, “spots” on her liver and a pleural effusion (fluid between the lungs and the chest wall).

I asked Olivia how the doctor had put it all together. “What do you mean?” She replied.

“You have 4 or 5 different things going on. You have pelvic pain, an ovarian cyst, a possible kidney cyst, some liver spots and a pleural effusion. When you have several signs and symptoms at one time, there is generally one primary cause of all of it.”

“They just said I had a ruptured ovarian cyst.”

I was starting to get a bit peeved with the process. “Let me explain something. In medical school we are taught the process of ‘Differential Diagnosis' which means we think of everything that might explain all of the signs and symptoms, and then we run a variety of tests and eliminate the least likely. A ‘symptom' is a subjective experience or problem that you report to the doctor. A ‘sign' is something objective that the doctor has determined through physical examination, laboratory data, x-rays, MRI's, etc. For example, just off the top of my head, I think you have endometriosis. That could explain all of the signs and symptoms, but let me go on-line and ‘Google' this one for you.” Internet information confirmed that endometriosis was definitely in the running as a possible cause.

I continued, “The doctor needs to be asking himself if the signs and symptoms are due to the seven medications you are taking, if you have an infection, if you have cancer (which is most unlikely), some kind of toxic, or allergic reaction, or a collagen vascular disease, such as lupus.”

“He just said that I had a ruptured ovarian cyst and he gave me some pain medication,” Olivia replied.

“Forgive me, but the doctor is an idiot. How can he ignore the pleural effusion, and the kidney and liver spots? Differential diagnosis is the cornerstone of how doctors diagnose and treat. You can't simply ignore four of the five problems as if they don't exist.”

A week later Olivia was back in the ER with no relief in the pain. She had seen a couple more doctors by now, and they concluded that the ovarian cyst had probably gotten infected, and so they sent her home with antibiotics. I groaned at this point in our conversation.

She called me again after she had been on the antibiotics, was still in a lot of pain, and was now getting panicky. Because one of the medications Olivia takes is an anti-depressant, the question of malingering or psychosomatic pain was suggested to her. I went back on-line and did some more research on endometriosis, and told her, “Everything is telling me that you have endometriosis, but then I'm a shrink, a holistic doc, but not an OB-GYN, family practitioner, or internist. I'm not supposed to know this, but let me continue. I think that sooner or later, your doctors are going to conclude that you have endometriosis and they will put you on birth control pills. I am warning you now, because I think that will happen. So, in case I am correct, I am also cautioning you that endometriosis does respond to progesterone, but is actually made worse by estrogen. The birth control pill has both estrogen and progesterone in it. If it comes up, ask your doctor to prescribe bio-identical progesterone, which he or she will need to order from a compounding pharmacy.”

Finally, I received the call I had been expecting. “Does this make sense you to? The doctor gave me birth control pills (BCP), said it would help with the pain, but that I did not have endometriosis.” I tried not to use the word “idiot” again, and replied, “No, it does not make sense. Your doctor thinks you do have endometriosis and is treating you for that with BCP's. He is basically not telling you the truth about what he is thinking. At any rate, how is the pill working for you?”

“The pain got better for a few days, but then I started to get depressed and moody, and the pain worsened again.” My friend is not assertive with her doctors and does not ask a lot of questions. She went back to the same doctor who thought she did not have endometriosis, who prescribed a second kind of BCP. Olivia responded the same way as she did with the first BCP.

Subsequently, Olivia saw an OB-GYN who diagnosed her with endometriosis—five weeks after her initial visit to the emergency room. Various recommendations were made, including BCP's and laparoscopic surgery. A family member suggested a hysterectomy. Out of frustration with the five medical doctors she had seen, and out of trust in Chinese Medicine, Olivia visited her Doctor of Oriental Medicine (DOM), who asked her a number of questions, and asked about specific symptoms not previously explored. The DOM was extremely accurate in her questioning and told Olivia that in four months she could cure the endometriosis, and that the herbs she would be taking were not hormonal in any way. Rather, they would strengthen her immune system and balance her body so that the health problem would naturally resolve. The DOM also gave her herbs for pain.

Finally, Olivia was feeling confident, feeling that she was in good hands and with someone who understood what was going on. She shared the news with me about the Chinese Medicine approach. After just a few days of herbal treatment, she experienced a noticeable decrease in pain. Everything the DOM told Olivia rang true for me, but when Olivia told one of her doctors about the herbs, the doctor blew a gasket, and said that the herbs could interfere with the blood levels of the medications she was taking. I again bit my tongue and refused to use the word “idiot.” “Olivia, the only herb I know of that has really destabilized people, and killed about twenty, is ephedra, and it has been pulled from the market. Your doctor is responding out of fear and ignorance. Did you know that medications cause about 300,000 deaths in America , which is about the third leading cause of death in America ? Did you know that the fifth leading cause of death is hospital-induced deaths? In other words, these are people who died mainly from infections that they caught while in the hospital, or due to an error in medication dosing.”

I was trying to paint a very clear picture for Olivia. Here is the picture. Herbs (ephedra) killed about twenty people, and it was on the six o'clock news. Proper use of medication kills about 300,000 people per year, and it has never made the evening news, as far as I know. This is part of the politics of Medicine, the Media, the AMA, FDA, State Medical Boards, and the Pharmaceutical Industry.

“Olivia, a doctor's first job is to inspire hope. That comes before diagnosis and treatment. Patients are also supposed to leave the doctor's office feeling better, regardless of the illness or treatment, because we are supposed to inspire hope. Your doctor really made a very big mistake by trying to destroy your belief in your Doctor of Oriental Medicine. Here is part of the problem. Doctors, including myself, feel a strong urge to always do something to help our patient. Oftentimes, in the face of ignorance and not knowing what to do, the doctor will still try to DO something, but that action might be to scare the hell out of you. He or she is still doing something. So, at some level, there really is a genuine concern for humanity that inspires such reactions. It is very difficult for doctors to say, ‘I don't know,' and it is very hard for many conventional doctors who know nothing about complementary and alternative treatments, to not go ballistic when their patient is choosing an alternative approach.”

This brings up a related point. Medical doctors will often make strong, definitive statements about subjects about which they have no knowledge, but they will act like they are experts. I do not mean to generalize this comment to all doctors, but I have experienced many this times. For example, I was having a discussion with my oldest brother, a psychiatrist, about chronic fatigue syndrome. He said, “There is absolutely no scientific data that CFS exists at all.” I replied, “If I email you URL's for five web sites loaded with hard data and facts about CFS, will you read it?” He replied that he would. I sent him those URL's. One was the University of Newcastle, Australia, whose research into CFS includes a 500-page book, and is perhaps the most extensive, in-depth, conclusive testing in the world. My brother never mentioned the conversation. It is highly unlikely that he read any of the data. He is not unusual.

Even well respected, famous doctors of Integrative Medicine have been known to make sweeping statements that are not backed up by any data. I once saw an interview of Dr. Andrew Weil on Larry King Live. A woman called in and asked Dr. Weil how he treats candidiasis. Dr. Weil responded, “There is no such thing as candidiasis. If you have a chronic intestinal problem, you need to see a gastroenterologist.” I immediately knew a few things about Dr. Weil, who has done some very good work in educating the public about health and wellness. But, I knew that he was not an “in-the-trenches” holistic doctor, because they see and treat systemic candida every day of their lives. I treat candida and base my diagnosis on history, stool samples, a urine test, and a blood test for anti-candida antibodies. Regardless of one's medical orientation, the error of making doctorly pronouncements without the facts to back it up is far too common, and is a great disservice to individuals who are suffering and society at large.

After two weeks under the care of the DOM, Olivia is dramatically better. Her pain is much less, she has returned to work, and has shaken off the fear and doubt instilled in her by the doctor who became quite emotional and negative about the use of herbs.

There are a number of issues raised by this story, too many issues on which to elaborate in this article. Many of you have experienced something like Olivia, and have not known exactly what was going on. The main purpose of this article is to introduce you to the thought process that doctors have drilled into them in medical school and which is supposed to be their guide in virtually all diagnosis and treatment. That process is called “differential diagnosis.” The doctor must weigh evidence of signs and symptoms, and then determine all the possibilities that could be causing the problem or illness. It is not okay for a doctor to dismiss a diagnosis because it seems unlikely. The doctor has to go through a process of eliminating one diagnosis after another, starting with the least likely, but most serious diagnoses. Doctors don't want to miss a rare, but potentially fatal illness. After taking a history and performing a physical exam, a doctor should have a list in his head of 3, 4, 5, or 6 possible causes. He or she then runs a variety of blood, urine, and stool tests, x-rays, MRI's, and whatever other diagnostic tools are available. After the test results are in, the doctor is able to start eliminating diagnoses from the list. I should mention that physical examination is not part of the process of differential diagnosis for all physicians. Psychiatric diagnosis is made by taking a history and by observing the patient's behavior, mood, speech, physical movements, gestures, thought process, interaction style, and more.

The process of differential diagnosis requires a doctor to tolerate uncertainty, something many doctors don't like. But, until all the facts are in, doctors do live with uncertainty. It is re-assuring to tell patients what is going on in a doctor's mind, which illnesses he is considering, which are most likely, which are least likely. The doctor may choose not to mention cancer or AIDS, for example, until the lab results have returned, as there are situations in which the mere mention of these illnesses will unnecessarily traumatize the patient.

The process of differential diagnosis is really an on-going experiment. Once the doctor has decided on the most likely diagnosis, he recommends treatment. The doctor may need to modify his diagnosis depending on how the patient responds to the treatment. If the right treatment was prescribed for the right illness, but the patient shows no improvement, the initial diagnosis may be incorrect.

In preparing this article, I reviewed my medical school text on differential diagnosis, written in 1970. I was surprised to read that many doctors fear going through the process of differential diagnosis, for they like to do something for their patient Right Now, and they don't like the uncertainty of the process, or the length of time they may be facing before they can confidently arrive at a diagnosis. In other words, many doctors come to premature closure. They zero in on one diagnosis and ignore other possibilities. This is certainly what Olivia went through. Of the five medical doctors she saw, as far as I can tell, none of them went through a systematic differential diagnosis. For one month, not one doctor attempted to draw a connection between the five different signs and symptoms.

As a health care consumer, you have the right to understand the expected process of differential diagnosis, and, like it or not, most of us will see an allopathic doctor at some point in life, no matter how much wheat grass we drink. If you are seeing a medical doctor now or will be in the future, it is your right to ask the doctor what his differential diagnosis is, which illness or cause is most likely and which is least likely. And it is your right to ask him why he is considering each diagnosis and what he will be doing to rule that diagnosis in or out.

And for those of you who are medical doctors, please join me in going back to the basics. Remember differential diagnosis. Take your time, regardless of time pressures, and tolerate the uncertainty of not knowing—until you know.

David Gersten, M.D. practices nutritional medicine and psychiatry out of his Encinitas office and can be reached at 760-633-3063. Please feel free to access 1,000 on-line pages about holistic health, amino acids, and nutritional therapy at


Dear Louise

Dear Louise,

I'm a breast cancer survivor, and I try to stay as stress-free as possible. But, of late, I've been under a lot of stress and have been having hiatal hernia and acid reflux problems. The probable cause and new thought pattern for these two conditions are not in your book Heal Your Body. Thus, I really would appreciate it if you would be kind enough to tell me a probable cause and new thought pattern for these two ailments. Thank you.

R.A., New York

Dear R.A.,

Fear. It's all fear. Dear one, you're scaring yourself with your own thoughts. Eckhart Tolle's brilliant book The Power of Now says it all when he talks about stress: “Stress is caused by being here but wanting to be there, or being in the present but wanting to be in the future. It's a split that tears you apart inside.”

Hiatal hernia is creating and carrying mental burdens that make it impossible for you to relax. The same with acid reflux—just fearful thoughts that tie your stomach up in knots. I probably sound like a broken record saying the same thing over and over, but most of our problems come from not allowing ourselves to breathe deeply and fully and refusing to stay in the now.

Many, many times during the day, and before you go to sleep, take slow, deep breaths. Bring your attention to the present moment. Don't think about the past or future. Say to yourself: In this moment, all is well. I am safe. There is nowhere I have to go and nothing I have to do. I relax my body and my mind. I am grateful for this moment. This will break the pattern of incessant worry.

You're far more than your worrisome, fearful thoughts. As you said, you're a survivor. And I say that you're a powerful, dynamite woman, and you can heal yourself! Be at peace, my dear.

Dear Louise,

I've had chronic fatigue/hypothyroidism for six years now, but I'm not healing. Since last year I've been having a recurring thought pop into my head: “I'm tired of my life.” Basically, I feel that my life is making me ill. I'm bored, and I want to change my life completely, but having low energy makes a change difficult. My subconscious is talking to me, so I know I need a change, but how can I combat this thought with something positive?

F.V., Sydney, Australia

Dear F.V.,

Of course you're tired of life. You've been disconnected from your emotions for a long time. This pattern usually begins in childhood. At home and in society, many of us receive the message that it's not okay to express certain feelings such as sadness and anger. We suppress or “depress” the so-called unacceptable feelings inside of us. We become cut off from our emotional energy and are left with a general feeling of fatigue and disconnection from life. We slow our bodies down and feel we're running on empty. At least 80 percent of all autoimmune disease (when the immune system attacks the body) occurs in women. Somewhere very deep within so many of our bodies there's some kind of destructive message that needs to be revealed and transformed. To break free of this pattern, it's helpful to establish a safe environment to reconnect with our feeling processes and begin to safely release stored anger, sadness, and other suppressed emotions. It's highly recommended and important to have qualified professional help in this process. An affirmation to use here is: It is safe to express all that is within me. I love, honor, and accept all aspects of who and what I am. As a result, I'm energized, expressed, and filled with joy!

Dear Louise,

I'm recognizing a pattern that's been present in my life since the '70s. It has to do with finances. It seems that there's always a theme of loss of employment and housing. The situation clears up and then comes around again. I'm willing to release this pattern and obtain, maintain, and sustain that which is mine by Divine right. Will you assist me in unveiling the cause of this pattern? Thank you, and God bless.

B.H., Tempe, Arizona

Dear B.H.,

At the top of a large sheet of paper, write: What I Believe about Money, Women, and Deserving. Then list everything you were taught or learned as a child about these subjects: what your parents believed, what your teachers said, what the church told you about keeping your place, and so on. Don't censor anything. If it comes up in your mind, it's part of your belief system. Take several days to get all of this out where you can look at it.

When you read it, you'll see that some of the things you learned were positive and helpful. However, as you look at the list, you'll discover many negative beliefs about the worthiness of women, and why you don't deserve to be prosperous. Turn every negative comment into a positive affirmation. For instance, “I will never amount to anything” could be turned into: “I have every right to be fulfilled and to be a success.” Or, turn: “Nobody wants me” into: “I am loved and respected wherever I go.”

Our thoughts create our reality, and your new thoughts can create a new reality for you! All is well!

If you would like Louise to answer your letter in this publication, please send it to: Dear Louise Column, c/o Hay House, Inc., P.O. Box 5100, Carlsbad, CA 92018-5100, or e-mail your letter to: (letters used in this column may be edited for length and clarity). Please visit Louise's website at: or the Hay House website at: